Flow PHP

WindowFunction extends FunctionTree, Describable

Methods

children() : array<int, FunctionTree>: Every operand of this node that is an expression, in constructor order.
describe() : null|Description
deterministic() : bool: True when this node and every node in children() produce the same value for the same input row.
fromDescription() : static
over() : static: Returns a copy bound to $window. Never mutates $this.
resolved() : bool: True when this node and every node in children() can answer returns().
returns() : Type<string|int, mixed>: An OptionalType return declares the produced column nullable; there is no nullable() peer.
toString() : string
values() : array<int, mixed>: One value per row of $partition, which is sorted by the window's ORDER BY.
window() : Window
withChildren() : static: A copy of this node with $children in place of children(): same count, same order, same per-element narrowing. Never mutates $this.

children()

Every operand of this node that is an expression, in constructor order.


    public
                    children() : array<int, FunctionTree>

Raw scalars, enums, Types and scope-introducing bodies are fields, not children.

Return values

array<int, FunctionTree>

describe()


    public
                    describe() : null|Description

Return values

null|Description —

null when this instance cannot cross a process boundary (a live client, a custom collaborator)

deterministic()

True when this node and every node in children() produce the same value for the same input row.


    public
                    deterministic() : bool

False for a generator (now(), uuid, a random string): a caller that evaluates the tree once per FILE or per partition instead of once per row must refuse a non-deterministic one.

Return values

bool

fromDescription()


    public
            static        fromDescription(array<string|int, mixed> $data, Rebuild $rebuild) : static

Parameters

$data : array<string|int, mixed>
$rebuild : Rebuild

Return values

static

over()

Returns a copy bound to $window. Never mutates $this.


    public
                    over(Window $window) : static

Parameters

$window : Window

Return values

static

resolved()

True when this node and every node in children() can answer returns().


    public
                    resolved() : bool

Return values

bool

returns()

An OptionalType return declares the produced column nullable; there is no nullable() peer.


    public
                    returns() : Type<string|int, mixed>

The frame contributes nothing to the type - Window is a field, not a parameter.

Return values

Type<string|int, mixed>

toString()


    public
                    toString() : string

Return values

string

values()

One value per row of $partition, which is sorted by the window's ORDER BY.


    public
                    values(Rows $partition, Backend $backend) : array<int, mixed>

Parameters

$partition : Rows
$backend : Backend

Return values

array<int, mixed>

window()


    public
                    window() : Window

Return values

Window

withChildren()

A copy of this node with $children in place of children(): same count, same order, same per-element narrowing. Never mutates $this.


    public
                    withChildren(array<int, FunctionTree> $children) : static

Parameters

$children : array<int, FunctionTree>

Return values

static